The test reveals if a patient has been infected by Helicobacter pylori (H.pylori), a common corkscrew shaped bacterium that burrows into the stomach's mucus lining. The infection can be eliminated with a simple combination of antibiotics and acid lowering drugs.
Professor David Forman told ECCO 11 - the European Cancer Conference in Lisbon that there was "persuasive evidence" from various studies linking H-pylori infection to stomach cancer. He added: "A recent meta-analysis shows that these are now consistent in showing an approximate three to sixfold increased risk of non-cardia stomach cancer in H.pylori positive individuals.
"This indicates that at least half of all non-cardia cancer 1 can be attributable to the infection and possibly a great deal more. Apart from smoking, very few established causes of cancer have been associated with an attributable risk of this magnitude".
But Professor Forman said that the case for universal screening for H.pylori infection for people at risk from cancer still had to be established. He explained: "The critical question concerns the extent to which H.pylori pre-cancerous changes will regress or be prevented from progressing after the eradication of H.pylori from the stomach".
In order to prove that eradication prevents gastric cancer, large numbers of patients (possibly several hundred thousand) would need to be recruited into intervention studies and followed up for 10 to 20 years.
Based at the University of Leeds, in the north of England, Professor Forman said that, for some people, controlling H.pylori infection would probably be easier to achieve than preventive measures requiring behavioural change - such as smoking, diet and excessive exposure to the sun.
He added: "It would also be cheaper than other screening interventions, such as breast screening and cervical cytology, requiring expensive technology and frequent repeat examinations. Evidence from preliminary intervention (screening) studies is now beginning to accumulate".
Stomach cancer accounts for approaching one million deaths worldwide each year. Most cases are diagnosed at an advanced stage, and, outside Japan, survival is notoriously poor - usually no more than 15 per cent at five years.
The discovery of H.pylori in the early 1980s represents one of the most important developments in the history of gastroenterology. The bacteria are not only associated with stomach cancer, but also inflammation of the stomach (gastritis) and ulcers. For many years, doctors blamed the typical symptoms of ulcers - burning stomach pain and nausea - on stress, believing that increased stress produced excessive amounts of acid. But in the past decade research has established that up to 90 per cent of gastritis and ulcers are caused not by stress or acid, but by H.pylori.
Abstract No. 916
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